title: The lipopolysaccharide of the mastitis isolate Escherichia coli strain 1303 comprises a novel O-antigen and the rare K-12 core type.
abstract: Mastitis represents one of the most significant health problems of dairy herds. The two major causative agents of this disease are Escherichia coli and Staphylococcus aureus. Of the first, its lipopolysaccharide (LPS) is thought to play a prominent role during infection. Here, we report the O-antigen (OPS, O-specific polysaccharide) structure of the LPS from bovine mastitis isolate E. coli 1303. The structure was determined utilizing chemical analyses, mass spectrometry, and 1D and 2D NMR spectroscopy methods. The O-repeating unit was characterized as -[→4)-β-D-Quip3NAc-(1→3)-α-L-Fucp2OAc-(1→4)-β-D-Galp-(1→3)-α-D-GalpNAc-(1→]- in which the O-acetyl substitution was non-stoichiometric. The nucleotide sequence of the O-antigen gene cluster of E. coli 1303 was also determined. This cluster, located between the gnd and galF genes, contains 13 putative open reading frames, most of which represent unknown nucleotide sequences that have not been described before. The O-antigen of E. coli 1303 was shown to substitute O-7 of the terminal LD-heptose of the K-12 core oligosaccharide. Interestingly, the non-OPS-substituted core oligosaccharide represented a truncated version of the K-12 outer core - namely terminal LD-heptose and glucose were missing; however, it possessed a third Kdo residue in the inner core. On the basis of structural and genetic data we show that the mastitis isolate E. coli 1303 represents a new serotype and possesses the K-12 core type, which is rather uncommon among human and bovine isolates.
authors.affiliation: Division of Structural Biochemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, D-23845 Borstel, Germany.
authors.forename: Katarzyna A
authors.initials: KA
authors.lastname: Duda
authors.affiliation: Division of Immunochemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, D-23845 Borstel, Germany.
authors.forename: Buko
authors.initials: B
authors.lastname: Lindner
authors.affiliation: Division of Medical and Biochemical Microbiology, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, D-23845 Borstel, Germany.
authors.forename: Helmut
authors.initials: H
authors.lastname: Brade
authors.affiliation: Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University of Göttingen, D-37077 Göttingen, Germany.|Institute for Molecular Infection Biology, Julius-Maximilians-University of Würzburg, D-97070 Würzburg, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Leimbach
authors.affiliation: Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University of Göttingen, D-37077 Göttingen, Germany.
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Brzuszkiewicz
authors.affiliation: Institute for Hygiene, University of Münster, D-48149 Münster, Germany.|Institute for Molecular Infection Biology, Julius-Maximilians-University of Würzburg, D-97070 Würzburg, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Dobrindt
authors.affiliation: Division of Structural Biochemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, D-23845 Borstel, Germany.
authors.forename: Otto
authors.initials: O
authors.lastname: Holst
mesh_terms: D000818:Animals; D001483:Base Sequence; D002240:Carbohydrate Sequence; D002417:Cattle; D004926:Escherichia coli / Q000737:chemistry* / Q000145:classification / Q000235:genetics / Q000276:immunology; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary; D005260:Female; D006801:Humans; D008070:Lipopolysaccharides / Q000737:chemistry* / Q000235:genetics; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008414:Mastitis, Bovine / Q000382:microbiology*; D008969:Molecular Sequence Data; D005810:Multigene Family; D019081:O Antigens / Q000737:chemistry* / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: C114999:K-12 lipopolysaccharide; D008070:Lipopolysaccharides; D019081:O Antigens